In agricultural production, there are needs for controlling various fungi pathogenic to plants, pests, weeds, and the like, and agricultural chemicals have hitherto been useful means therefor. However, there have been problems in that some compounds are phytotoxic for plants, and particularly for the crop plants to which the agricultural chemicals are applied, even though these compounds have excellent activity as agricultural chemicals, or in that even compounds which are not phytotoxic are not effective enough for practical use. Accordingly, production of compounds which are greatly effective as agricultural chemicals and which have little phytotoxicity has always been demanded.
Japanese Patent No. 2514823 and Japanese Patent Application, First Publication (Kokai), No. 1-283270, disclose that 2,6-dichloroisonicotinic acid derivatives having specific structures are active in protecting crop plants from pathogenic microorganisms. However, these compounds are phytotoxic for some types of crops, although these compounds were effective.
On the other hand, 2,6-dichloro-4-pyridinemethanol, to which the present invention relates, can be synthesized, for example, by bringing about a reduction reaction using 2,6-dichloroisonicotinic acid or an ester thereof as a starting material. (J. Prakt. Chem., Vol. 134, pp. 177-187 (1932); West German Patent Publication No. 3,615,293) However, neither a 2,6-dichloro-4-pyridinemethanol derivative according to the present invention nor use of 2,6-dichloro-4-pyridinemethanol and a 2,6-dichloro-4-pyridinemethanol derivative as an agricultural chemical has been known.
The object to be achieved by the present invention is to provide a novel compound with which there is little possibility of phytotoxicity for crop plants, and which is greatly effective in controlling various plant diseases caused by viruses pathogenic to plants, by bacteria, and by molds, and to provide agricultural chemicals, particularly agents for controlling plant diseases, containing this compound, i.e., 2,6-dichloro-4-pyridinemethanol, and/or a benzoic acid ester thereof as an active ingredient.